From 26a2a7f4a65331f519ced628dfe7e0fa7b3ce513 Mon Sep 17 00:00:00 2001
From: Jim MacArthur <jim.macarthur@codethink.co.uk>
Date: Thu, 4 Feb 2016 17:18:30 +0000
Subject: [PATCH] Allow CHARACTER literals in assignments and data statements

Warnings are raised when this happens.

Enable using -fdec-char-as-int or -fdec
---
 gcc/fortran/arith.c                                | 94 +++++++++++++++++++++-
 gcc/fortran/arith.h                                |  4 +
 gcc/fortran/expr.c                                 |  5 ++
 gcc/fortran/gfortran.texi                          | 24 ++++++
 gcc/fortran/intrinsic.c                            | 32 +++++++-
 gcc/fortran/invoke.texi                            | 17 ++--
 gcc/fortran/lang.opt                               |  5 ++
 gcc/fortran/options.c                              |  1 +
 gcc/fortran/resolve.c                              |  9 +++
 gcc/fortran/simplify.c                             | 29 ++++++-
 gcc/fortran/trans-const.c                          |  6 +-
 .../dec_char_conversion_in_assignment_1.f90        | 61 ++++++++++++++
 .../dec_char_conversion_in_assignment_2.f90        | 61 ++++++++++++++
 .../dec_char_conversion_in_assignment_3.f90        | 61 ++++++++++++++
 .../gfortran.dg/dec_char_conversion_in_data_1.f90  | 69 ++++++++++++++++
 .../gfortran.dg/dec_char_conversion_in_data_2.f90  | 69 ++++++++++++++++
 .../gfortran.dg/dec_char_conversion_in_data_3.f90  | 69 ++++++++++++++++
 .../gfortran.dg/dec_char_conversion_in_data_4.f90  |  9 +++
 gcc/testsuite/gfortran.dg/hollerith5.f90           |  5 +-
 gcc/testsuite/gfortran.dg/hollerith_legacy.f90     |  2 +-
 .../gfortran.dg/no_char_to_numeric_assign.f90      | 21 +++++
 21 files changed, 634 insertions(+), 19 deletions(-)
 create mode 100644 gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_1.f90
 create mode 100644 gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_2.f90
 create mode 100644 gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_3.f90
 create mode 100644 gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_1.f90
 create mode 100644 gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_2.f90
 create mode 100644 gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_3.f90
 create mode 100644 gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_4.f90
 create mode 100644 gcc/testsuite/gfortran.dg/no_char_to_numeric_assign.f90

diff --git a/gcc/fortran/arith.c b/gcc/fortran/arith.c
index ff279db4992..ad071c71c3f 100644
--- a/gcc/fortran/arith.c
+++ b/gcc/fortran/arith.c
@@ -2510,9 +2510,9 @@ hollerith2representation (gfc_expr *result, gfc_expr *src)
 
   if (src_len > result_len)
     {
-      gfc_warning (0,
-		   "The Hollerith constant at %L is too long to convert to %qs",
-		   &src->where, gfc_typename(&result->ts));
+      gfc_warning (OPT_Wcharacter_truncation, "The Hollerith constant at %L "
+		   "is truncated in conversion to %qs", &src->where,
+		   gfc_typename(&result->ts));
     }
 
   result->representation.string = XCNEWVEC (char, result_len + 1);
@@ -2527,6 +2527,36 @@ hollerith2representation (gfc_expr *result, gfc_expr *src)
 }
 
 
+/* Helper function to set the representation in a character conversion.
+   This assumes that the ts.type and ts.kind of the result have already
+   been set.  */
+
+static void
+character2representation (gfc_expr *result, gfc_expr *src)
+{
+  size_t src_len, result_len;
+  int i;
+  src_len = src->value.character.length;
+  gfc_target_expr_size (result, &result_len);
+
+  if (src_len > result_len)
+    gfc_warning (OPT_Wcharacter_truncation, "The character constant at %L is "
+		 "is truncated in conversion to %s", &src->where,
+		 gfc_typename(&result->ts));
+
+  result->representation.string = XCNEWVEC (char, result_len + 1);
+
+  for (i = 0; i < MIN (result_len, src_len); i++)
+    result->representation.string[i] = (char) src->value.character.string[i];
+
+  if (src_len < result_len)
+    memset (&result->representation.string[src_len], ' ',
+	    result_len - src_len);
+
+  result->representation.string[result_len] = '\0'; /* For debugger  */
+  result->representation.length = result_len;
+}
+
 /* Convert Hollerith to integer. The constant will be padded or truncated.  */
 
 gfc_expr *
@@ -2542,6 +2572,19 @@ gfc_hollerith2int (gfc_expr *src, int kind)
   return result;
 }
 
+/* Convert character to integer. The constant will be padded or truncated. */
+
+gfc_expr *
+gfc_character2int (gfc_expr *src, int kind)
+{
+  gfc_expr *result;
+  result = gfc_get_constant_expr (BT_INTEGER, kind, &src->where);
+
+  character2representation (result, src);
+  gfc_interpret_integer (kind, (unsigned char *) result->representation.string,
+			 result->representation.length, result->value.integer);
+  return result;
+}
 
 /* Convert Hollerith to real. The constant will be padded or truncated.  */
 
@@ -2558,6 +2601,21 @@ gfc_hollerith2real (gfc_expr *src, int kind)
   return result;
 }
 
+/* Convert character to real. The constant will be padded or truncated.  */
+
+gfc_expr *
+gfc_character2real (gfc_expr *src, int kind)
+{
+  gfc_expr *result;
+  result = gfc_get_constant_expr (BT_REAL, kind, &src->where);
+
+  character2representation (result, src);
+  gfc_interpret_float (kind, (unsigned char *) result->representation.string,
+		       result->representation.length, result->value.real);
+
+  return result;
+}
+
 
 /* Convert Hollerith to complex. The constant will be padded or truncated.  */
 
@@ -2574,6 +2632,21 @@ gfc_hollerith2complex (gfc_expr *src, int kind)
   return result;
 }
 
+/* Convert character to complex. The constant will be padded or truncated.  */
+
+gfc_expr *
+gfc_character2complex (gfc_expr *src, int kind)
+{
+  gfc_expr *result;
+  result = gfc_get_constant_expr (BT_COMPLEX, kind, &src->where);
+
+  character2representation (result, src);
+  gfc_interpret_complex (kind, (unsigned char *) result->representation.string,
+			 result->representation.length, result->value.complex);
+
+  return result;
+}
+
 
 /* Convert Hollerith to character.  */
 
@@ -2609,3 +2682,18 @@ gfc_hollerith2logical (gfc_expr *src, int kind)
 
   return result;
 }
+
+/* Convert character to logical. The constant will be padded or truncated.  */
+
+gfc_expr *
+gfc_character2logical (gfc_expr *src, int kind)
+{
+  gfc_expr *result;
+  result = gfc_get_constant_expr (BT_LOGICAL, kind, &src->where);
+
+  character2representation (result, src);
+  gfc_interpret_logical (kind, (unsigned char *) result->representation.string,
+			 result->representation.length, &result->value.logical);
+
+  return result;
+}
diff --git a/gcc/fortran/arith.h b/gcc/fortran/arith.h
index 39366caaba1..85c8b8cef41 100644
--- a/gcc/fortran/arith.h
+++ b/gcc/fortran/arith.h
@@ -77,7 +77,11 @@ gfc_expr *gfc_hollerith2real (gfc_expr *, int);
 gfc_expr *gfc_hollerith2complex (gfc_expr *, int);
 gfc_expr *gfc_hollerith2character (gfc_expr *, int);
 gfc_expr *gfc_hollerith2logical (gfc_expr *, int);
+gfc_expr *gfc_character2int (gfc_expr *, int);
+gfc_expr *gfc_character2real (gfc_expr *, int);
+gfc_expr *gfc_character2complex (gfc_expr *, int);
 gfc_expr *gfc_character2character (gfc_expr *, int);
+gfc_expr *gfc_character2logical (gfc_expr *, int);
 
 #endif /* GFC_ARITH_H  */
 
diff --git a/gcc/fortran/expr.c b/gcc/fortran/expr.c
index c508890d68d..f04d19f7409 100644
--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -3722,6 +3722,11 @@ gfc_check_assign (gfc_expr *lvalue, gfc_expr *rvalue, int conform,
 	  || rvalue->ts.type == BT_HOLLERITH)
 	return true;
 
+      if (flag_dec_char_conversions && (gfc_numeric_ts (&lvalue->ts)
+	  || lvalue->ts.type == BT_LOGICAL)
+          && rvalue->ts.type == BT_CHARACTER)
+	return true;
+
       if (lvalue->ts.type == BT_LOGICAL && rvalue->ts.type == BT_LOGICAL)
 	return true;
 
diff --git a/gcc/fortran/gfortran.texi b/gcc/fortran/gfortran.texi
index 02d30e19660..8341bcda199 100644
--- a/gcc/fortran/gfortran.texi
+++ b/gcc/fortran/gfortran.texi
@@ -1600,6 +1600,7 @@ additional compatibility extensions along with those enabled by
 * Unary operators::
 * Implicitly convert LOGICAL and INTEGER values::
 * Hollerith constants support::
+* Character conversion::
 * Cray pointers::
 * CONVERT specifier::
 * OpenMP::
@@ -1955,6 +1956,29 @@ obtained by using the @code{TRANSFER} statement, as in this example.
 @end smallexample
 
 
+@node Character conversion
+@subsection Character conversion
+@cindex conversion, to character
+
+Allowing character literals to be used in a similar way to Hollerith constants
+is a non-standard extension.
+
+Character literals can be used in @code{DATA} statements and assignments with
+numeric (@code{INTEGER}, @code{REAL}, or @code{COMPLEX}) or @code{LOGICAL}
+variables. Like Hollerith constants they are copied byte-wise fashion. The
+constant will be padded with spaces or truncated to fit the size of the
+variable in which it is stored.
+
+Examples:
+@smallexample
+      integer*4 x
+      data x / 'abcd' /
+
+      x = 'A'       ! Will be padded.
+      x = 'ab1234'  ! Will be truncated.
+@end smallexample
+
+
 @node Cray pointers
 @subsection Cray pointers
 @cindex pointer, Cray
diff --git a/gcc/fortran/intrinsic.c b/gcc/fortran/intrinsic.c
index ac5af10a775..9cfbac363bf 100644
--- a/gcc/fortran/intrinsic.c
+++ b/gcc/fortran/intrinsic.c
@@ -4025,6 +4025,28 @@ add_conversions (void)
 	  add_conv (BT_LOGICAL, gfc_logical_kinds[j].kind,
 		    BT_INTEGER, gfc_integer_kinds[i].kind, GFC_STD_LEGACY);
 	}
+
+  /* Flang allows character conversions similar to Hollerith conversions
+     - the first characters will be turned into ascii values. */
+  if (flag_dec_char_conversions)
+    {
+      /* Character-Integer conversions.  */
+      for (i = 0; gfc_integer_kinds[i].kind != 0; i++)
+	add_conv (BT_CHARACTER, gfc_default_character_kind,
+		  BT_INTEGER, gfc_integer_kinds[i].kind, GFC_STD_LEGACY);
+      /* Character-Real conversions.  */
+      for (i = 0; gfc_real_kinds[i].kind != 0; i++)
+	add_conv (BT_CHARACTER, gfc_default_character_kind,
+		  BT_REAL, gfc_real_kinds[i].kind, GFC_STD_LEGACY);
+      /* Character-Complex conversions.  */
+      for (i = 0; gfc_real_kinds[i].kind != 0; i++)
+	add_conv (BT_CHARACTER, gfc_default_character_kind,
+		  BT_COMPLEX, gfc_real_kinds[i].kind, GFC_STD_LEGACY);
+      /* Character-Logical conversions.  */
+      for (i = 0; gfc_logical_kinds[i].kind != 0; i++)
+	add_conv (BT_CHARACTER, gfc_default_character_kind,
+		  BT_LOGICAL, gfc_logical_kinds[i].kind, GFC_STD_LEGACY);
+    }
 }
 
 
@@ -5185,8 +5207,16 @@ gfc_convert_type_warn (gfc_expr *expr, gfc_typespec *ts, int eflag, int wflag)
 			     gfc_typename (&from_ts), gfc_dummy_typename (ts),
 			     &expr->where);
 	}
+      else if (flag_dec_char_conversions && from_ts.type == BT_CHARACTER
+	       && (gfc_numeric_ts (ts) || ts->type == BT_LOGICAL))
+	{
+	  const char *type_name = is_char_constant ? gfc_typename (expr)
+						   : gfc_typename (&from_ts);
+	  gfc_warning_now (OPT_Wconversion, "Conversion from %s to %s at %L",
+			   type_name, gfc_typename (ts), &expr->where);
+	}
       else
-        gcc_unreachable ();
+	gcc_unreachable ();
     }
 
   /* Insert a pre-resolved function call to the right function.  */
diff --git a/gcc/fortran/invoke.texi b/gcc/fortran/invoke.texi
index fa60effdbfe..4d01ddeaa07 100644
--- a/gcc/fortran/invoke.texi
+++ b/gcc/fortran/invoke.texi
@@ -118,9 +118,9 @@ by type.  Explanations are in the following sections.
 @xref{Fortran Dialect Options,,Options controlling Fortran dialect}.
 @gccoptlist{-fall-intrinsics -fallow-argument-mismatch -fallow-invalid-boz @gol
 -fbackslash -fcray-pointer -fd-lines-as-code -fd-lines-as-comments -fdec @gol
--fdec-structure-fdec-intrinsic-ints -fdec-static -fdec-math -fdec-include @gol
--fdec-format-defaults -fdec-blank-format-item -fdefault-double-8 @gol
--fdefault-integer-8 -fdefault-real-8 -fdefault-real-10 @gol
+-fdec-char-conversions -fdec-structure -fdec-intrinsic-ints -fdec-static @gol
+-fdec-math -fdec-include -fdec-format-defaults -fdec-blank-format-item @gol
+-fdefault-double-8 -fdefault-integer-8 -fdefault-real-8 -fdefault-real-10 @gol
 -fdefault-real-16 -fdollar-ok -ffixed-line-length-@var{n} @gol
 -ffixed-line-length-none -fpad-source -ffree-form @gol
 -ffree-line-length-@var{n} -ffree-line-length-none -fimplicit-none @gol
@@ -272,14 +272,19 @@ For details on GNU Fortran's implementation of these extensions see the
 full documentation.
 
 Other flags enabled by this switch are:
-@option{-fdollar-ok} @option{-fcray-pointer} @option{-fdec-structure}
-@option{-fdec-intrinsic-ints} @option{-fdec-static} @option{-fdec-math}
-@option{-fdec-include} @option{-fdec-blank-format-item}
+@option{-fdollar-ok} @option{-fcray-pointer} @option{-fdec-char-conversions}
+@option{-fdec-structure} @option{-fdec-intrinsic-ints} @option{-fdec-static}
+@option{-fdec-math} @option{-fdec-include} @option{-fdec-blank-format-item}
 @option{-fdec-format-defaults}
 
 If @option{-fd-lines-as-code}/@option{-fd-lines-as-comments} are unset, then
 @option{-fdec} also sets @option{-fd-lines-as-comments}.
 
+@item -fdec-char-conversions
+@opindex @code{fdec-char-conversions}
+Enable the use of character literals in assignments and data statements
+for non-character variables.
+
 @item -fdec-structure
 @opindex @code{fdec-structure}
 Enable DEC @code{STRUCTURE} and @code{RECORD} as well as @code{UNION},
diff --git a/gcc/fortran/lang.opt b/gcc/fortran/lang.opt
index 2cfc76df2ab..a6e73e1292d 100644
--- a/gcc/fortran/lang.opt
+++ b/gcc/fortran/lang.opt
@@ -456,6 +456,11 @@ fdec-blank-format-item
 Fortran Var(flag_dec_blank_format_item)
 Enable the use of blank format items in format strings.
 
+fdec-char-conversions
+Fortran Var(flag_dec_char_conversions)
+Enable the use of character literals in assignments and data statements
+for non-character variables.
+
 fdec-include
 Fortran Var(flag_dec_include)
 Enable legacy parsing of INCLUDE as statement.
diff --git a/gcc/fortran/options.c b/gcc/fortran/options.c
index 771c10e4985..6d5bc0655f8 100644
--- a/gcc/fortran/options.c
+++ b/gcc/fortran/options.c
@@ -76,6 +76,7 @@ set_dec_flags (int value)
   SET_BITFLAG (flag_dec_include, value, value);
   SET_BITFLAG (flag_dec_format_defaults, value, value);
   SET_BITFLAG (flag_dec_blank_format_item, value, value);
+  SET_BITFLAG (flag_dec_char_conversions, value, value);
 }
 
 /* Finalize DEC flags.  */
diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index 93f2d0aa761..c824a6b7ac1 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -10689,6 +10689,15 @@ resolve_ordinary_assign (gfc_code *code, gfc_namespace *ns)
   lhs = code->expr1;
   rhs = code->expr2;
 
+  if ((gfc_numeric_ts (&lhs->ts) || lhs->ts.type == BT_LOGICAL)
+      && rhs->ts.type == BT_CHARACTER
+      && rhs->expr_type != EXPR_CONSTANT)
+    {
+      gfc_error ("Cannot convert %s to %s at %L", gfc_typename (rhs),
+		 gfc_typename (lhs), &rhs->where);
+      return false;
+    }
+
   /* Handle the case of a BOZ literal on the RHS.  */
   if (rhs->ts.type == BT_BOZ)
     {
diff --git a/gcc/fortran/simplify.c b/gcc/fortran/simplify.c
index fa5aefe20c6..2eb1943c3ee 100644
--- a/gcc/fortran/simplify.c
+++ b/gcc/fortran/simplify.c
@@ -8522,10 +8522,31 @@ gfc_convert_constant (gfc_expr *e, bt type, int kind)
       break;
 
     case BT_CHARACTER:
-      if (type == BT_CHARACTER)
-	f = gfc_character2character;
-      else
-	goto oops;
+      switch (type)
+	{
+	case BT_INTEGER:
+	  f = gfc_character2int;
+	  break;
+
+	case BT_REAL:
+	  f = gfc_character2real;
+	  break;
+
+	case BT_COMPLEX:
+	  f = gfc_character2complex;
+	  break;
+
+	case BT_CHARACTER:
+	  f = gfc_character2character;
+	  break;
+
+	case BT_LOGICAL:
+	  f = gfc_character2logical;
+	  break;
+
+	default:
+	  goto oops;
+	}
       break;
 
     default:
diff --git a/gcc/fortran/trans-const.c b/gcc/fortran/trans-const.c
index 432d12bf168..e4df0a7b1a5 100644
--- a/gcc/fortran/trans-const.c
+++ b/gcc/fortran/trans-const.c
@@ -25,6 +25,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "coretypes.h"
 #include "tree.h"
 #include "gfortran.h"
+#include "options.h"
 #include "trans.h"
 #include "fold-const.h"
 #include "stor-layout.h"
@@ -331,8 +332,9 @@ gfc_conv_constant_to_tree (gfc_expr * expr)
 			gfc_build_string_const (expr->representation.length,
 						expr->representation.string));
 	  if (!integer_zerop (tmp) && !integer_onep (tmp))
-	    gfc_warning (0, "Assigning value other than 0 or 1 to LOGICAL"
-			 " has undefined result at %L", &expr->where);
+	    gfc_warning (OPT_Wsurprising, "Assigning value other than 0 or 1 "
+		         "to LOGICAL has undefined result at %L",
+			 &expr->where);
 	  return fold_convert (gfc_get_logical_type (expr->ts.kind), tmp);
 	}
       else
diff --git a/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_1.f90 b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_1.f90
new file mode 100644
index 00000000000..d504f92fbbc
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_1.f90
@@ -0,0 +1,61 @@
+! { dg-do run }
+! { dg-options "-fdec -Wsurprising -Wcharacter-truncation" }
+!
+! Modified by Mark Eggleston <mark.eggleston@codethink.com>
+!
+program test
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  a = '1234'
+  b = '1234'
+  c = '12341234'
+  d = '1234'     ! { dg-warning "undefined result" }
+  e = 4h1234
+  f = 4h1234
+  g = 8h12341234
+  h = 4h1234     ! { dg-warning "undefined result" }
+  
+  if (a.ne.e) stop 1
+  if (b.ne.f) stop 2
+  if (c.ne.g) stop 3
+  if (d.neqv.h) stop 4
+
+  ! padded values
+  a = '12'
+  b = '12'
+  c = '12234'
+  d = '124'   ! { dg-warning "undefined result" }
+  e = 2h12
+  f = 2h12
+  g = 5h12234
+  h = 3h123   ! { dg-warning "undefined result" }
+
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+
+  ! truncated values
+  a = '123478'       ! { dg-warning "truncated in" }
+  b = '123478'       ! { dg-warning "truncated in" }
+  c = '12341234987'  ! { dg-warning "truncated in" }
+  d = '1234abc'      ! { dg-warning "truncated in|undefined result" }
+  e = 6h123478       ! { dg-warning "truncated in" }
+  f = 6h123478       ! { dg-warning "truncated in" }
+  g = 11h12341234987 ! { dg-warning "truncated in" }
+  h = 7h1234abc      ! { dg-warning "truncated in|undefined result" }
+
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+
+end program
+
diff --git a/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_2.f90 b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_2.f90
new file mode 100644
index 00000000000..737ddc664de
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_2.f90
@@ -0,0 +1,61 @@
+! { dg-do run }
+! { dg-options "-fdec-char-conversions -std=legacy -Wcharacter-truncation -Wsurprising" }
+!
+! Modified by Mark Eggleston <mark.eggleston@codethink.com>
+!
+program test
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  a = '1234'
+  b = '1234'
+  c = '12341234'
+  d = '1234'     ! { dg-warning "undefined result" }
+  e = 4h1234
+  f = 4h1234
+  g = 8h12341234
+  h = 4h1234     ! { dg-warning "undefined result" }
+  
+  if (a.ne.e) stop 1
+  if (b.ne.f) stop 2
+  if (c.ne.g) stop 3
+  if (d.neqv.h) stop 4
+
+  ! padded values
+  a = '12'
+  b = '12'
+  c = '12234'
+  d = '124'   ! { dg-warning "undefined result" }
+  e = 2h12
+  f = 2h12
+  g = 5h12234
+  h = 3h123   ! { dg-warning "undefined result" }
+
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+
+  ! truncated values
+  a = '123478'       ! { dg-warning "truncated in" }
+  b = '123478'       ! { dg-warning "truncated in" }
+  c = '12341234987'  ! { dg-warning "truncated in" }
+  d = '1234abc'      ! { dg-warning "truncated in|undefined result" }
+  e = 6h123478       ! { dg-warning "truncated in" }
+  f = 6h123478       ! { dg-warning "truncated in" }
+  g = 11h12341234987 ! { dg-warning "truncated in" }
+  h = 7h1234abc      ! { dg-warning "truncated in|undefined result" }
+
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+
+end program
+
diff --git a/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_3.f90 b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_3.f90
new file mode 100644
index 00000000000..0ec494c4a92
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_assignment_3.f90
@@ -0,0 +1,61 @@
+! { dg-do run }
+! { dg-options "-fdec -fno-dec-char-conversions" }
+!
+! Modified by Mark Eggleston <mark.eggleston@codethink.com>
+!
+program test
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  a = '1234'     ! { dg-error "Cannot convert" }
+  b = '1234'     ! { dg-error "Cannot convert" }
+  c = '12341234' ! { dg-error "Cannot convert" }
+  d = '1234'     ! { dg-error "Cannot convert" }
+  e = 4h1234
+  f = 4h1234
+  g = 8h12341234
+  h = 4h1234
+  
+  if (a.ne.e) stop 1
+  if (b.ne.f) stop 2
+  if (c.ne.g) stop 3
+  if (d.neqv.h) stop 4
+
+  ! padded values
+  a = '12'    ! { dg-error "Cannot convert" }
+  b = '12'    ! { dg-error "Cannot convert" }
+  c = '12234' ! { dg-error "Cannot convert" }
+  d = '124'   ! { dg-error "Cannot convert" }
+  e = 2h12
+  f = 2h12
+  g = 5h12234
+  h = 3h123
+
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+
+  ! truncated values
+  a = '123478'       ! { dg-error "Cannot convert" }
+  b = '123478'       ! { dg-error "Cannot convert" }
+  c = '12341234987'  ! { dg-error "Cannot convert" }
+  d = '1234abc'      ! { dg-error "Cannot convert" }
+  e = 6h123478       !
+  f = 6h123478       !
+  g = 11h12341234987 !
+  h = 7h1234abc      !
+
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+
+end program
+
diff --git a/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_1.f90 b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_1.f90
new file mode 100644
index 00000000000..c493be9314b
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_1.f90
@@ -0,0 +1,69 @@
+! { dg-do run }
+! { dg-options "-fdec -Wsurprising" }
+!
+! Modified by Mark Eggleston <mark.eggleston@codethink.com>
+!
+
+subroutine normal
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '1234', '1234', '12341234', '1234' / ! { dg-warning "undefined result" }
+  data e, f, g, h / 4h1234, 4h1234, 8h12341234, 4h1234 / ! { dg-warning "undefined result" }
+  
+  if (a.ne.e) stop 1
+  if (b.ne.f) stop 2
+  if (c.ne.g) stop 3
+  if (d.neqv.h) stop 4
+end subroutine
+
+subroutine padded
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '12', '12', '12334', '123' / ! { dg-warning "undefined result" }
+  data e, f, g, h / 2h12, 2h12, 5h12334, 3h123 / ! { dg-warning "undefined result" }
+  
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+end subroutine
+
+subroutine truncated
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '123478', '123478', '1234123498', '12345' /  ! { dg-warning "too long|undefined result" }
+  data e, f, g, h / 6h123478, 6h123478, 10h1234123498, 5h12345 / ! { dg-warning "too long|undefined result" }
+  
+  if (a.ne.e) stop 9
+  if (b.ne.f) stop 10
+  if (c.ne.g) stop 11
+  if (d.neqv.h) stop 12
+end subroutine
+
+program test
+  call normal
+  call padded
+  call truncated
+end program
+
diff --git a/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_2.f90 b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_2.f90
new file mode 100644
index 00000000000..c7d8e241cec
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_2.f90
@@ -0,0 +1,69 @@
+! { dg-do run }
+! { dg-options "-fdec-char-conversions -std=legacy -Wsurprising" }
+!
+! Modified by Mark Eggleston <mark.eggleston@codethink.com>
+!
+
+subroutine normal
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '1234', '1234', '12341234', '1234' / ! { dg-warning "undefined result" }
+  data e, f, g, h / 4h1234, 4h1234, 8h12341234, 4h1234 / ! { dg-warning "undefined result" }
+  
+  if (a.ne.e) stop 1
+  if (b.ne.f) stop 2
+  if (c.ne.g) stop 3
+  if (d.neqv.h) stop 4
+end subroutine
+
+subroutine padded
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '12', '12', '12334', '123' / ! { dg-warning "undefined result" }
+  data e, f, g, h / 2h12, 2h12, 5h12334, 3h123 / ! { dg-warning "undefined result" }
+  
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+end subroutine
+
+subroutine truncated
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '123478', '123478', '1234123498', '12345' /  ! { dg-warning "too long|undefined result" }
+  data e, f, g, h / 6h123478, 6h123478, 10h1234123498, 5h12345 / ! { dg-warning "too long|undefined result" }
+  
+  if (a.ne.e) stop 9
+  if (b.ne.f) stop 10
+  if (c.ne.g) stop 11
+  if (d.neqv.h) stop 12
+end subroutine
+
+program test
+  call normal
+  call padded
+  call truncated
+end program
+
diff --git a/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_3.f90 b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_3.f90
new file mode 100644
index 00000000000..e7d084b5ffc
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_3.f90
@@ -0,0 +1,69 @@
+! { dg-do run }
+! { dg-options "-fdec -fno-dec-char-conversions" }
+!
+! Modified by Mark Eggleston <mark.eggleston@codethink.com>
+!
+
+subroutine normal
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '1234', '1234', '12341234', '1234' / ! { dg-error "Incompatible types" }
+  data e, f, g, h / 4h1234, 4h1234, 8h12341234, 4h1234 /
+  
+  if (a.ne.e) stop 1
+  if (b.ne.f) stop 2
+  if (c.ne.g) stop 3
+  if (d.neqv.h) stop 4
+end subroutine
+
+subroutine padded
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '12', '12', '12334', '123' / ! { dg-error "Incompatible types" }
+  data e, f, g, h / 2h12, 2h12, 5h12334, 3h123 /
+  
+  if (a.ne.e) stop 5
+  if (b.ne.f) stop 6
+  if (c.ne.g) stop 7
+  if (d.neqv.h) stop 8
+end subroutine
+
+subroutine truncated
+  integer(4) :: a
+  real(4) :: b
+  complex(4) :: c
+  logical(4) :: d
+  integer(4) :: e
+  real(4) :: f
+  complex(4) :: g
+  logical(4) :: h
+
+  data a, b, c, d / '123478', '123478', '1234123498', '12345' /  ! { dg-error "Incompatible types" }
+  data e, f, g, h / 6h123478, 6h123478, 10h1234123498, 5h12345 /
+  
+  if (a.ne.e) stop 9
+  if (b.ne.f) stop 10
+  if (c.ne.g) stop 11
+  if (d.neqv.h) stop 12
+end subroutine
+
+program test
+  call normal
+  call padded
+  call truncated
+end program
+
diff --git a/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_4.f90 b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_4.f90
new file mode 100644
index 00000000000..6eff27e14bc
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/dec_char_conversion_in_data_4.f90
@@ -0,0 +1,9 @@
+! { dg-do compile }
+! { dg-options "-fdec -Wconversion" }
+!
+! Ensure that character type name is correctly reported.
+
+program test
+  integer(4) x
+  data x / 'ABCD' / ! { dg-warning "CHARACTER\\(4\\) to INTEGER\\(4\\)" }
+end program
diff --git a/gcc/testsuite/gfortran.dg/hollerith5.f90 b/gcc/testsuite/gfortran.dg/hollerith5.f90
index ebd0a117c4f..d17f9ae40cf 100644
--- a/gcc/testsuite/gfortran.dg/hollerith5.f90
+++ b/gcc/testsuite/gfortran.dg/hollerith5.f90
@@ -1,8 +1,9 @@
        ! { dg-do compile }
+       ! { dg-options "-Wsurprising" }
        implicit none
        logical b
        b = 4Habcd ! { dg-warning "has undefined result" }
        end
 
-! { dg-warning "Hollerith constant" "const" { target *-*-* } 4 }
-! { dg-warning "Conversion" "conversion" { target *-*-* } 4 }
+! { dg-warning "Hollerith constant" "const" { target *-*-* } 5 }
+! { dg-warning "Conversion" "conversion" { target *-*-* } 5 }
diff --git a/gcc/testsuite/gfortran.dg/hollerith_legacy.f90 b/gcc/testsuite/gfortran.dg/hollerith_legacy.f90
index c3322498345..9d7e989b552 100644
--- a/gcc/testsuite/gfortran.dg/hollerith_legacy.f90
+++ b/gcc/testsuite/gfortran.dg/hollerith_legacy.f90
@@ -1,5 +1,5 @@
 ! { dg-do compile }
-! { dg-options "-std=legacy" }
+! { dg-options "-std=legacy -Wsurprising" }
 ! PR15966, PR18781 & PR16531
 implicit none
 complex(kind=8) x(2) 
diff --git a/gcc/testsuite/gfortran.dg/no_char_to_numeric_assign.f90 b/gcc/testsuite/gfortran.dg/no_char_to_numeric_assign.f90
new file mode 100644
index 00000000000..3c60403160a
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/no_char_to_numeric_assign.f90
@@ -0,0 +1,21 @@
+! { dg-do compile }
+! { dg-options "-fdec-char-conversions" }
+!
+! Test character variables can not be assigned to numeric and
+! logical variables.
+!
+! Test case contributed by Mark Eggleston <mark.eggleston@codethink.com>
+!
+program test
+  integer a
+  real b
+  complex c
+  logical d
+  character e
+
+  e = "A"
+  a = e ! { dg-error "Cannot convert" }
+  b = e ! { dg-error "Cannot convert" }
+  c = e ! { dg-error "Cannot convert" }
+  d = e ! { dg-error "Cannot convert" }
+end program
-- 
2.11.0

